JPH0742410U - Engine intake throttle device - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] A simple three-way solenoid valve can be used to control the opening of the throttle valve in two stages, fully open, half open, and fully closed, according to the engine operating state. Also, ensure a good response of the throttle valve during sudden acceleration. In an intake throttle device including a fluid pressure type actuator 9, pressure chambers of the actuator 9 are divided into first and second pressure chambers.
A mechanical valve 12 is provided, which is connected to a fluid pressure supply source through the nipples 10 and 11 of FIG. 1 by piping and closes the second nipple 11 in the stroke region of the actuator 9 that exceeds the half-open position of the throttle valve 8. A first three-way solenoid valve 18, a second three-way solenoid valve 19, in the middle of the piping of the actuator 9,
While interposing the third three-way solenoid valve 20, a control unit 21 for controlling these solenoid valves according to the engine operating state is provided.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention relates to an intake throttle device for an engine.

[0002]

[Prior art]

 For example, a throttle valve is installed in the intake passage of an engine that uses light oil, alcohol, etc. as a fuel, and its opening is controlled according to the engine operating state so that a good combustion state can be obtained even in the low load range. Those which have been made are known (Japanese Utility Model Publication No. 62-52247, Japanese Utility Model Publication No. 62-95144, etc.).

[0003]

[Problems to be solved by the device]

 By the way, in such a conventional example, a diaphragm type is often adopted as an actuator for driving the throttle valve in the intake passage. In that case, intake pulsation acts on the throttle valve, so an orifice is formed in the actuator operating pressure passage to prevent the diaphragm from being damaged early by the input vibration. Since it takes time to release the negative pressure of the diaphragm, there was a problem that the response of the throttle valve was greatly impaired.

The present invention aims to effectively solve such a problem.

[0005]

[Means for Solving the Problems]

 Therefore, in an intake throttle device equipped with a fluid pressure type actuator that opens and closes the throttle valve in the engine intake passage, the pressure chamber of the actuator is connected to the fluid pressure supply source via the first and second nipples, and the throttle valve A mechanical valve that closes the second nipple in the actuator stroke area that exceeds the half-open position is provided, and an inlet port on the upstream side and an exhaust port on the atmosphere release side are provided in the supply port to the first nipple side in the middle of the actuator piping. A first three-way solenoid valve that selectively communicates with a second three-way solenoid valve that selectively communicates an upstream inlet port with the first three-way solenoid valve side supply port and the second nipple side supply port. Valve and a third three-way solenoid valve that selectively communicates the upstream introduction port and the atmosphere-release side exhaust port with the supply port to the second three-way solenoid valve side. To one, providing the control unit that controls these electromagnetic valves according to the engine operating state.

[0006]

[Action]

 Therefore, by using a simple three-way solenoid valve instead of an expensive control valve with a linear opening characteristic, the throttle valve opening can be controlled in two stages, fully open, half open, and fully closed depending on the engine operating condition. It becomes possible to do. When switching the throttle valve to full open, in addition to opening the first nipple from the first three-way solenoid valve to the atmosphere, connect the second nipple to the second three-way solenoid valve and the third three-way solenoid valve. Even if an orifice is formed in the first nipple, the negative pressure in the pressure chamber is quickly released by opening the atmosphere via the through hole, so that good responsiveness can be secured even during sudden start or sudden acceleration. .

[0007]

【Example】

 In FIG. 1, the engine 1 is provided with an EGR passage 4 that connects the exhaust passage 2 and the intake passage 3 and an EGR valve 5 that controls the EGR amount thereof. A diaphragm type actuator 6 drives the EGR valve 5, and its pressure chamber is connected to a vacuum pump of the vehicle through a third three-way solenoid valve 20 which will be described later. A throttle valve 8 is provided in the middle of the engine intake passage 3 (upstream of the connection with the EGR passage 4), and a diaphragm actuator 9 is provided which is connected to an outer lever of the throttle valve 8 via a rod.

The actuator 9 is provided with first and second nipples 10 and 11 that open into its pressure chamber, and as shown in FIG. 2, a mechanical mechanism that closes the second nipple 11 in a stroke region that exceeds the half-open position of the throttle valve 8. The valve 12 is installed. 13 is a return spring of the diaphragm 14, 15 is a return spring of the valve 12, 16 is a guide for slidably supporting the valve 12 (formed on the diaphragm 14 toward the second nipple 11), and 17 is intake air. An orifice (useful for stabilizing the valve 12) for damping input vibration of the diaphragm 14 due to pulsation is shown.

The pressure chamber of the actuator 9 is pipe-connected from the first and second nipples 10 and 11 to the vacuum pump side. In the middle of the piping, there is a one-way three-way solenoid valve 18 that connects the supply port to the first nipple 10 side to the upstream introduction port when the power is turned on and the supply port to the discharge port to the atmosphere when the power is turned off. A second three-way solenoid valve 19 that connects the supply port to the second nipple 11 side to the upstream introduction port when energization is on, and communicates the introduction port to the first three-way solenoid valve 18 side when energization is off, A third three-way solenoid valve 20 that communicates the supply port to the second three-way solenoid valve 19 side with the introduction port on the vacuum pump side when the power is turned on and the supply port to the exhaust port on the atmosphere release side when the power is off is provided. To be equipped.

A control unit 21 controls each of the three-way solenoid valves 18 to 20 in accordance with the engine operating state, and receives engine cooling water temperature, engine rotational speed, and accelerator opening detection signals. Then, the control unit 21 opens and closes the EGR valve 5 and the throttle valve 8 based on these detection signals as shown in FIG.

That is, in the low load region, based on the operation mode 1, the first and third three-way solenoid valves 18, 20 are turned on and the second three-way solenoid 19 is turned off. As a result, negative pressure is supplied from the vacuum pump through the third three-way solenoid valve 20 to the actuator 6 side of the EGR valve 5 and the actuator 9 side of the throttle valve 8. Therefore, the actuator 6 opens the EGR valve 5 to recirculate a part of the exhaust gas from the engine 1 from the exhaust passage 2 to the intake passage 3 through the EGR passage 4.

Further, the actuator 9 causes the throttle valve 8 to move to the intake passage 3 by the negative pressure supplied from the third three-way solenoid valve 20 to the first nipple 10 via the second and first three-way solenoid valves 19 and 18. Rotate in the closing direction of. The valve 12 hits the second nipple 11 during the stroke, but the first nipple 10 supplies the load, so the diaphragm 14 compresses the return spring 15 of the valve 12 and fully closes the throttle valve 8. The pressure chamber is further reduced to (minimum opening of the intake passage 3).

When shifting to an intermediate region between low load and medium load, based on the operation mode 2, the third and second three-way solenoid valves 20 and 19 are turned on and the first three-way solenoid valve 18 is turned off. As a result, the actuator 6 opens the EGR valve 5 with the negative pressure from the third three-way solenoid valve 20. Further, the actuator 9 receives the load from the second three-way solenoid valve 19 to the second nipple 11, and is opened to the atmosphere from the first nipple 10 through the first three-way solenoid valve 18, so that the valve 12 is opened. Since the diaphragm 14 is displaced to the stroke position for opening and closing the second nipple 11, the throttle valve 8 holds the intake passage 3 in a half-open state.

In the medium load range, the third three-way solenoid valve 20 is turned on and the second and first three-way solenoid valves 19, 18 are turned off based on the operation mode 3. As a result, the actuator 6 opens the EGR valve 5 by the negative pressure from the third three-way solenoid valve 20, and the actuator 9 is opened to the atmosphere from the first nipple 10 via the first three-way solenoid valve 18 (the first one). Since the second three-way solenoid valve 19 is switched to the first three-way solenoid valve 18 side), the return spring 13 rotates the throttle valve 8 to the fully open position of the intake passage 3.

When shifting to the high load region, the throttle valve 8 is fully opened based on the operation mode 5 and the three-way solenoid valves 81 to 20 are turned off in order to close the EGR valve 5. As a result, the actuator 6 is opened to the atmosphere via the third three-way solenoid valve 20, and the actuator 9 is opened to the atmosphere via the first three-way solenoid valve 18.

When switching the throttle valve 8 to the fully open state when the vehicle suddenly starts or accelerates, the first three-way solenoid valve 18 is turned off based on the operation mode 4 prior to the execution of the operation mode 5. The second three-way solenoid valve 19 is turned on for a predetermined time. As a result, the negative pressure of the diaphragm 14 is released from the first nipple 10 side to the atmosphere via the first three-way solenoid valve 18, and the second nipple 11 causes the second and third three-way solenoid valves to be released. Since it is opened to the atmosphere through the valves 19 and 20, the negative pressure quickly escapes from the pressure chamber regardless of the orifice 17 formed in the first nipple 10, so that the throttle valve 8 has a high responsiveness and a fully open position. Rotate to.

With such a configuration, by using a simple three-way solenoid valve instead of an expensive control valve having a linear opening characteristic, the opening of the throttle valve 8 can be fully opened or half-opened depending on the engine operating state. It becomes possible to control in two stages of fully closed. When switching the throttle valve 8 from full close or half open to full open at the time of sudden start and sudden acceleration of the vehicle, since the operation mode 4 is temporarily performed, in addition to the first nipple 10 side provided with the orifice 17, As a result, the atmosphere is released from the side of the second nipple 11 as well, so that good response of the throttle valve 8 can be secured.

Since the third three-way solenoid valve 20 also functions as a control valve that selectively supplies the negative pressure and the atmospheric pressure to the actuator 6 of the EGR valve 5, the device for performing the EGR and the intake throttle is, of course, used. Therefore, the number of three-way solenoid valves can be reduced.

[0019]

[Effect of device]

 In short, according to the present invention, in the intake throttle device including the fluid pressure type actuator that opens and closes the throttle valve of the engine intake passage, the pressure chamber of the actuator is connected to the fluid pressure supply source through the first and second nipples. In addition, a mechanical valve that closes the second nipple in the stroke region of the actuator that exceeds the half-open position of the throttle valve is provided, and the supply port to the first nipple side is connected to the upstream introduction port in the middle of the actuator piping. The first three-way solenoid valve that selectively communicates with the discharge port on the atmosphere open side, the supply port to the first three-way solenoid valve side and the supply port to the second nipple side, and the upstream introduction port selectively The second three-way solenoid valve in communication with the supply port to the second three-way solenoid valve side is selectively connected to the upstream introduction port and the atmosphere release side discharge port. While the three-way solenoid valve of No. 3 is installed, a control unit that controls these solenoid valves according to the engine operating state is provided. It can be controlled in two stages: fully open, half open, and fully closed. In addition, the throttle valve can be switched to full open with good response when the vehicle suddenly starts or accelerates.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a sectional view showing an actuator of a throttle valve.

FIG. 3 is an operation mode table for explaining control contents of the control unit.

[Explanation of symbols]

 3 Engine Intake Passage 8 Throttle Valve 9 Diaphragm Actuator 10 First Nipple 11 Second Nipple 12 Valve 14 Diaphragm 17 Orifice 18 First Three-Way Solenoid Valve 19 Second Three-Way Solenoid Valve 20 Third Three-Way Solenoid Valve

Claims (1)

[Scope of utility model registration request] 1. An intake throttle device comprising a fluid pressure type actuator for opening and closing a throttle valve in an engine intake passage,
The pressure chamber of the actuator is connected to the fluid pressure supply source through the first and second nipples by piping, and a mechanical valve that closes the second nipple in a stroke region of the actuator that exceeds the half-open position of the throttle valve is provided. Supplying to the first three-way solenoid valve side, and the first three-way solenoid valve that selectively connects the upstream introduction port and the atmosphere release side discharge port to the first nipple side supply port in the middle of the piping A second three-way solenoid valve that selectively connects the upstream side introduction port to the port and the second nipple side supply port;
A third three-way solenoid valve that selectively communicates the upstream-side introduction port and the atmosphere-opening-side exhaust port with the supply port to the second three-way solenoid valve side is interposed, while these solenoid valves are in the engine operating state. An intake throttle device for an engine, which is provided with a control unit for controlling according to the.